I found something else that might be helpful. But as I understand it, this does not apply to your spouse and your dependent children. Here is the link where I got this info:
http://www.cic.gc.ca/english/pdf/kits/guides/5482E.PDFTable 1 — Low Income Cut-off
(Effective until December 31, 2011)Size of Family Unit
Minimum necessary income
1 person (the sponsor)
$22,229
2 persons
$27,674
3 persons
$34,022
4 persons
$41,307
5 persons
$46,850
6 persons
$52,838
7 persons
$58,827
More than 7 persons, for each additional person, add
$5,989